Following the lead of successful Italy and Greece, Turkey is now aggressively seeking the return of smuggled antiquities to the country from several U.S. museums. According to this article, Turkey has “supporting evidence and has threatened to halt all loans of art to those institutions until they respond to the claims.” The Met has already been denied loans.
The majority of the works were acquired by the museums relatively recently – since the 1960s – with little or no documented provenance, which suggests that they could have come from illicit excavations.